package com.qww.exec02;

public class Exec02 {
    public static void main(String[] args) {
        B b = new B("hello");
        System.out.println(b.s);
    }
}

class B {
    String s;
    B() {
        System.out.println("无参数构造调用...");
    }
    B(String s) {
        System.out.println("有参数构造调用...");
        this.s = s;
    }
}
